1. Field of the Invention
The present invention relates to automatic door openers and other systems for opening or closing a door. More particularly, the present invention relates to a mechanical arm system for opening a door, especially a Sensitive Compartmented Information Facility (SCIF) door, in which no component of the mechanical arm system is mounted on, or makes permanent contact with, the door.
2. Background Art
Automatic door openers, for many different applications, are well known in the art. Automatic door openers may be equipped on doors of public facilities to allow passage through the doorway of people without their manual operation. Automatic door openers may incorporate hydraulic, pneumatic, and electromechanical devices. For example, a conventional automatic door opener for opening or closing a door includes an a control unit, an actuator driving a drive shaft and an articulated opener arm extending between the drive shaft and the door. An end of the opener arm is either permanently mounted on one of the door or the door frame, with the actuator and drive shaft combination mounted on the other of the door frame or the door. The opener arm responds to movement of the drive shaft to extend or contract so as to move the door to an open or closed position, respectively. The control unit may include adjustable timers and sensors to control the movement of the door, and to identify when an obstacle is encountered in the door's pathway. Typically, the door opener must complete its opening process of placing the door in the open position before closure of the door can be initiated.
Consequently, such a conventional door opener is unacceptable for use with a SCIF door. The requirements for an SCIF door are dictated by the U.S. government, and two of these requirements provide that, except for the lock, key bypass, a door closer, and crash-put bar, nothing additional can be installed which makes permanent contact with the door and that the door must be able to return to its closed state, quickly, at any point in its forward opening cycle.
What is needed, therefore, is a mechanism for automatically opening a door, in which none of the mechanism's components are mounted on the door itself, and further allows for closure of the door from any position during the door opening process. The present invention satisfies these and other needs, as will be made apparent by the description of the present invention that follows.